diff --git a/src/naive/date/mod.rs b/src/naive/date/mod.rs
index d0ac747a6b..9b1a35c965 100644
--- a/src/naive/date/mod.rs
+++ b/src/naive/date/mod.rs
@@ -122,7 +122,7 @@ impl arbitrary::Arbitrary<'_> for NaiveDate {
 
 impl NaiveDate {
     pub(crate) fn weeks_from(&self, day: Weekday) -> i32 {
-        (self.ordinal() as i32 - self.weekday().num_days_from(day) as i32 + 6) / 7
+        (self.ordinal() as i32 - self.weekday().days_since(day) as i32 + 6) / 7
     }
 
     /// Makes a new `NaiveDate` from year, ordinal and flags.
diff --git a/src/weekday.rs b/src/weekday.rs
index 19ecc8043a..ec3421ab5d 100644
--- a/src/weekday.rs
+++ b/src/weekday.rs
@@ -105,9 +105,9 @@ impl Weekday {
     /// assert_eq!(Sun.days_since(Tue), 5);
     /// assert_eq!(Wed.days_since(Sun), 3);
     /// ```
-    pub fn days_since(&self, other: Weekday) -> u32 {
-        let lhs = self.num_days_from_monday();
-        let rhs = other.num_days_from_monday();
+    pub const fn days_since(&self, other: Weekday) -> u32 {
+        let lhs = *self as u32;
+        let rhs = other as u32;
         if lhs < rhs {
             7 + lhs - rhs
         } else {
@@ -122,7 +122,7 @@ impl Weekday {
     /// `w.number_from_monday()`: | 1     | 2     | 3     | 4     | 5     | 6     | 7
     #[inline]
     pub const fn number_from_monday(&self) -> u32 {
-        self.num_days_from(Weekday::Mon) + 1
+        self.days_since(Weekday::Mon) + 1
     }
 
     /// Returns a day-of-week number starting from Sunday = 1.
@@ -132,7 +132,7 @@ impl Weekday {
     /// `w.number_from_sunday()`: | 2     | 3     | 4     | 5     | 6     | 7     | 1
     #[inline]
     pub const fn number_from_sunday(&self) -> u32 {
-        self.num_days_from(Weekday::Sun) + 1
+        self.days_since(Weekday::Sun) + 1
     }
 
     /// Returns a day-of-week number starting from Monday = 0.
@@ -155,7 +155,7 @@ impl Weekday {
     /// ```
     #[inline]
     pub const fn num_days_from_monday(&self) -> u32 {
-        self.num_days_from(Weekday::Mon)
+        self.days_since(Weekday::Mon)
     }
 
     /// Returns a day-of-week number starting from Sunday = 0.
@@ -165,17 +165,7 @@ impl Weekday {
     /// `w.num_days_from_sunday()`: | 1     | 2     | 3     | 4     | 5     | 6     | 0
     #[inline]
     pub const fn num_days_from_sunday(&self) -> u32 {
-        self.num_days_from(Weekday::Sun)
-    }
-
-    /// Returns a day-of-week number starting from the parameter `day` (D) = 0.
-    ///
-    /// `w`:                        | `D`   | `D+1` | `D+2` | `D+3` | `D+4` | `D+5` | `D+6`
-    /// --------------------------- | ----- | ----- | ----- | ----- | ----- | ----- | -----
-    /// `w.num_days_from(wd)`:      | 0     | 1     | 2     | 3     | 4     | 5     | 6
-    #[inline]
-    pub(crate) const fn num_days_from(&self, day: Weekday) -> u32 {
-        (*self as u32 + 7 - day as u32) % 7
+        self.days_since(Weekday::Sun)
     }
 }
 
@@ -316,34 +306,28 @@ mod tests {
     use super::Weekday;
 
     #[test]
-    fn test_num_days_from() {
+    fn test_days_since() {
         for i in 0..7 {
             let base_day = Weekday::try_from(i).unwrap();
 
-            assert_eq!(base_day.num_days_from_monday(), base_day.num_days_from(Weekday::Mon));
-            assert_eq!(base_day.num_days_from_sunday(), base_day.num_days_from(Weekday::Sun));
-
-            assert_eq!(base_day.num_days_from(base_day), 0);
-
-            assert_eq!(base_day.num_days_from(base_day.pred()), 1);
-            assert_eq!(base_day.num_days_from(base_day.pred().pred()), 2);
-            assert_eq!(base_day.num_days_from(base_day.pred().pred().pred()), 3);
-            assert_eq!(base_day.num_days_from(base_day.pred().pred().pred().pred()), 4);
-            assert_eq!(base_day.num_days_from(base_day.pred().pred().pred().pred().pred()), 5);
-            assert_eq!(
-                base_day.num_days_from(base_day.pred().pred().pred().pred().pred().pred()),
-                6
-            );
-
-            assert_eq!(base_day.num_days_from(base_day.succ()), 6);
-            assert_eq!(base_day.num_days_from(base_day.succ().succ()), 5);
-            assert_eq!(base_day.num_days_from(base_day.succ().succ().succ()), 4);
-            assert_eq!(base_day.num_days_from(base_day.succ().succ().succ().succ()), 3);
-            assert_eq!(base_day.num_days_from(base_day.succ().succ().succ().succ().succ()), 2);
-            assert_eq!(
-                base_day.num_days_from(base_day.succ().succ().succ().succ().succ().succ()),
-                1
-            );
+            assert_eq!(base_day.num_days_from_monday(), base_day.days_since(Weekday::Mon));
+            assert_eq!(base_day.num_days_from_sunday(), base_day.days_since(Weekday::Sun));
+
+            assert_eq!(base_day.days_since(base_day), 0);
+
+            assert_eq!(base_day.days_since(base_day.pred()), 1);
+            assert_eq!(base_day.days_since(base_day.pred().pred()), 2);
+            assert_eq!(base_day.days_since(base_day.pred().pred().pred()), 3);
+            assert_eq!(base_day.days_since(base_day.pred().pred().pred().pred()), 4);
+            assert_eq!(base_day.days_since(base_day.pred().pred().pred().pred().pred()), 5);
+            assert_eq!(base_day.days_since(base_day.pred().pred().pred().pred().pred().pred()), 6);
+
+            assert_eq!(base_day.days_since(base_day.succ()), 6);
+            assert_eq!(base_day.days_since(base_day.succ().succ()), 5);
+            assert_eq!(base_day.days_since(base_day.succ().succ().succ()), 4);
+            assert_eq!(base_day.days_since(base_day.succ().succ().succ().succ()), 3);
+            assert_eq!(base_day.days_since(base_day.succ().succ().succ().succ().succ()), 2);
+            assert_eq!(base_day.days_since(base_day.succ().succ().succ().succ().succ().succ()), 1);
         }
     }